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1.
利用从珠江莲花山河段采集的淡水和有大洋海过滤后，按不同盐度混后，模拟河口咸淡水交汇区重金属在水中各微粒级的分配特征，实验结果表明，在各种盐度条件下，Ｆｅ，Ａｌ，Ｃｕ，Ｐｂ，Ｚｎ和Ｃｄ主要以粒径＞１．０μｍ和＜０．２２μｍ的微粒存在于水中，在加入Ｆｅ＾３＋，Ａｌ＾３＋模拟实验中，重金属绝大部分含量形成粒径＞１．０μｍ的微粒，其中Ｆｅ达９９％以上，Ｃｕ，Ｐｂ，约９５％，Ａｌ约有７０％－９０％，Ｃｄ约４ 相似文献
2.
金属离子对牙鲆仔鱼的毒性影响 总被引：4，自引：0，他引：4
本文用静水生物实验法进行了Ｚｎ、Ｃｕ、Ｐｂ、Ｃｄ金属离子对海洋底栖鱼类牙鲆（Ｐａｒａｌｉｃｈｔｈｙｓｏｌｉｖａｃｅｕｓ）仔鱼的成活影响研究。结果表明：Ｃｕ（２＋）、Ｃｄ（２＋）、Ｚｎ（２＋）、Ｐｂ（２＋）对牙鲆仔鱼２４ｈＬＣ（５０）分别为１．１４、１．５１、４．６８、５．８９ｍｇ／ｄｍ３．４８ｈＬＣ（５０）分别为０．１４、０．８３、０．９９、３．４７ｍｇ／ｄｍ３．７２ｈＬＣ（５０）分别为０．０６、０．３６、０．７１、０．９３ｍｇ／ｄｍ３．９６ｈＬＣ（５０）分别为０．０２、０．１４、０．４３、０．５３ｍｇ／ｄｍ３．Ｃｕ（２＋）对牙鲆仔鱼的毒性最大，Ｐｂ（２＋）的毒性最小．４种金属离子对仔鱼的毒性顺序依次为：Ｃｕ（２＋）＞Ｃｄ（２＋）＞Ｚｎ（２＋）＞Ｐｂ（２＋）． 相似文献
3.
珠江口水域微表层中的痕量金属 总被引：2，自引：0，他引：2
采用自制滚筒式自动采样器采样，研究了珠江口水域微表层中Ｆｅ，Ｍｎ，Ｃｕ，Ｐｂ，Ｚｎ，Ｃｄ的含量，分布变化及富集状况。并通过颗粒痕量金属／颗粒Ｆｅ比值计算，探讨了痕量金属的来源。结果表明：Ｃｕ，Ｐｂ，Ｚｎ，Ｃｄ在微表层平均富集系数分别为２．３，１．４，３．０和１．９颗粒态Ｆｅ，Ｍｎ的平均富集系数为１．１和０．９。各种金属有明显的季节和空间变化，有各种不同的来源。 相似文献
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江阴岛海域溶解态Cu,Pb,Cd的含量及其与营养盐的关系 总被引：2，自引：0，他引：2
首次报道了福建省福清市江阴岛海域溶解态Ｃｕ，Ｐｂ，Ｃｄ的含量，并探讨了它们与营养盐的关系。１９９０年５月溶解态Ｃｕ，Ｐｂ，Ｃｄ的平均含量分别为０．８２、０．３８０、０．０２２μｇ／ｄｍ＾２，１０月的平均含量分别为０．７６、０．３８２、０．０３２μｇ／ｄｍ＾２。其５月溶解态Ｃｕ与无机氮Ｎ，硅酸盐间的线性回归相关式分别为Ｃｕ、（μｇ／ｄｍ＾３）＝０．４３８＋０．０３７７Ｎ（μｇ／ｄｍ＾３）、Ｃｕ（μｇ 相似文献
6.
台湾海峡西部海域大气中金属的特征 总被引：9，自引：2，他引：7
１９９１－１９９３年,收集了台湾海峡西部海域上空大气中的１８１个颗粒样品和２个颗粒分级样品。采用原子分光光度法分析了其中的颗粒金属Ａｌ、Ｆｅ、Ｃｕ、ｐｂ、Ｃｄ,Ｎａ,台湾海峡西部海域大气中颗粒金属Ｆｅ、Ｃｕ、ｐｂ、Ｃｄ的含量明显低于大陆城市大气中的含量,大气颗粒物中Ａｌ、Ｃｕ,Ｐｂ显示了明显的年变化,Ａｌ、Ｆｅ、Ｃｕ、Ｐｂ、Ｃｄ表现出明显的季节变化,干季大于湿季,影响大气颗粒金属元素浓度季节变化的 相似文献
7.
金属离子对长毛对虾酸性磷酸酶的影响 总被引：8，自引：0，他引：8
本文研究几种金属离子分别对健康虾和病虾酸性磷酸酶ＡＣＰａｓｅ（ＥＣ３．１．３．２）活性的影响。结果表明,Ｎｉ＾２＋、Ｍｇ＾２＋、Ｃｄ＾２＋对酶无明显抑制作用,Ｚｎ＾２＋、Ｃｕ＾２＋、Ｈｇ＾２＋对酶活力抑制明显。当Ｈｇ＾２＋离子浓度达０．５ｍｍｏｌ／ｄｍ＾２时,酶活力被抑制９６％和９５％;各金属离子对酶的抑制强度依次为Ｈｇ＾２＋〉Ｃｕ＾２＋〉Ｚｎ＾２＋〉Ｐｂ＾２＋〉Ｃｄ＾２＋、Ｍｇ＾２＋〉Ｎｉ＾２＋ 相似文献
8.
铜对鲫鱼血清生化成分的影响 总被引：12，自引：0，他引：12
本文通过分析鲫鱼血清生化成分含量的变化，研究Ｃｕ对鲫鱼的致毒效应。试验结果表明，（１）血清Ｎａ＾＋，Ｃｌ＾－含量随Ｃｕ浓度的升高而增加，在水中Ｃｕ浓度为３．９１μｍｏｌ／Ｌ时达到最大值，而血清Ｋ＾＋不受Ｃｕ影响。（２）血清胆固醇，球蛋白含量和ＧＯＴ，ＡＬＰ酶活性均在Ｃｕ浓度为０．７８μｍｏｌ／Ｌ时达到最高值，若再增加Ｃｕ浓度，血清胆固醇，球蛋白含量有所下降，但仍高于对照组，而ＧＯＴ，ＡＬＰ酶活性却 相似文献
9.
应用水汽化学的方法学和理论,研究南,北极雪,冰,水中的Ｚｎ＾２＋等离子,南北,极雪,冰,水中Ｚｎ＾２＋,Ｃｄ＾２＋,Ｐｂ＾２＋,Ｃｕ＾２＋,Ｓｎ＾４＋,Ｂｉ＾３＋离子含量的空间变化很小,与水汽化学原理计算的离子总平均含量Ｚｎ＾２＋,５．０μｇ／Ｌ,Ｐｂ＾２＋＋０．０３０μｇ／Ｌ,Ｃｕ＾２＋＋０．７０μｇ／Ｌ,Ｓｎ＾４＋＋０．９９μｇ／Ｌ,Ｂｉ＾３＋＋０．１８μｇ／Ｌ相一致。南北极Ｚｎ＾２＋等离子处 相似文献
10.
海水pH对疏浚物中重金属释放的影响 总被引：2，自引：0，他引：2
对厦门员当湖污染疏浚物中的Ｃｄ，Ｃｕ和Ｐｂ在不同ｐＨ的天然海水中溶出的模拟研究结果表明：在ｐＨ为５．０，６．５，８．３条件下，疏浚物中的Ｃｄ，Ｃｕ，Ｐｂ的释放率分别为８０％－９４％，４％－９％和１．０％－２．２％；在相同条件下，Ｃｄ，Ｃｕ，Ｐｂ的释放量（释放量）均随ｐＨ值增大而减少，释放量的顺序为Ｃｄ＞Ｃｕ＞Ｐｂ。讨论了ｐＨ对释放作用的影响及释放过程所遵循的动力学规律。 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
12.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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15.
《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
16.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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18.
Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
19.
Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献
20.
The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included. 相似文献